Detonating cord is used extensively in the petroleum exploration and production industry to initiate the detonation of explosive materials in various types of downhole tools, such as perforating tools, setting tools, and the like. The borehole sites at which such tools and associated detonating cord are used are scattered worldwide, as are the relevant manufacturing, supply and service facilities. Consequently it is highly desirable that such tools, as well as the associated detonating cord be shipped by air from the supply facility location to the location of the using facility. However, the regulations governing the shipment of explosive materials by air are quite stringent. Basically, the regulations require that the explosive materials be packaged such that any ignition or detonation shall be confined to that container and will not propogate to another container.
U.S. Pat. No. 4,586,602, which is assigned to the assignee of the present invention, discloses a detonating cord transport system that meets the above mentioned air shipping regulations for explosive materials. The detonating cord transport system of the '602 patent is, however, susceptible to some improvements that will serve to increase economy and efficiency, particularly regarding the amount of labor required in packaging detonating cord and the quantity of detonating cord per package.
It is the objective of the present invention to provide improved systems and methods for packaging detonating cord in containers in such manner as to qualify for shipment by commercial air carriers in the United States of America and internationally.